SearchButtonMode enum

Represents the search mode for SearchButton, determining how search queries are handled and submitted.

Live mode provides real-time updates to the search callback as the user types, sending:

• An empty string when the search box opens but is empty.
• A trimmed non-empty string for active queries.
• null when the search box closes, indicating no active search.

This mode is ideal for dynamically filtering lists or content in components like Selector or Collection.

Transactional mode only submits non-empty queries upon pressing enter or the close button, closing the search box immediately. Empty submissions are ignored, ensuring the callback receives only valid search terms without nulls.

This mode suits scenarios where search triggers a separate action, such as opening a Dialog or navigating to a results screen, integrating well with PopupMenu for combined search-and-select interfaces or MutableText for editable search history.